Comparação da mínima diferença detectável em corredoras

Abstract

Classical psychophysics considers it possible to quantify the response to the stimulus, being defined as a continuum of detectable stimuli within a human response by its sensory perception. The concept of minimal detectable difference “only perceptible difference – JND” is applied to physical exercise, by measuring the magnitude of the difference between a perceived sensory stimulus compared to the standard stimulus, which may be the difference measured above (JND-A) or below (JND-B). Purpose: To describe the Minimal Detectable Difference of women brokers. Method: The present study is made up of 22 runners with a previous experience of 2 years. The research design consists of two experimental sessions, and the first experimental session is called “Estimation” in order to determine the physiological, perceptual parameters, and level of cardiorespiratory conditioning (lowfitness and highfitness), as well as to determine the standard intensity. After 48 hours, a second experimental session, called “Just Noticeable Difference” – JND, was conducted, consisting of four sets of running on a treadmill, lasting five minutes each, with a five-minute recovery interval between sets. This session determined the individual’s perceptual acuity, or also known as the total magnitude of the minimum total detectable difference (JND); as well as above (JND-A) and below (JND-B) the standard stimulus of 70%VO2max. Results: The participants were 22 women with a mean age of 36,6 years (± 8,29); Average Body Mass of 55,5kg (± 5,45); Average height of 1,62m (± 6,25); Mean BMI 20,2 (± 5,01). The description of the perceptive acuity measured by the variation of the oxygen consumption above and below the standard stimulus (SS) in each attempt of the JND shows: VO2max JND-Above average of 1,90 (± 1,75); 70%VO2max JND-Above average of 4,01 (± 3,65); VO2max JND-Below mean of -0,21 (± 1,55); 70%VO2max JNDBelow average of -0,49 (± 3,31). In conclusion, knowing the magnitude of the JND can help coaches and athletes in monitoring training and competitions, in the sense that, by listening to the body’s signals, the individual is able to adjust the rhythm during the task, especially the microvariations that depend only on perceptible emotions, in this way, the JND is a new tool, which should be used to improve the performance of Endurance athletes.